Last name Ривай (Rivai 
, Rivay 
, Rivaj 
) , in the entire world, is a common cognomen. The family name Ривай is characteristic of Indonesia, where it is quite a rare surname, Maldives, and Malaysia, where it is a rare surname. Not in comparison with a country's population, it is the most numerous in Indonesia, India, and Malaysia. Much less frequently, Ривай is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Rivai | Indonesia, Malaysia, United States, India, Democratic Republic of the Congo |
| Rivay | Indonesia, Mexico, United States, India, Brazil |
| Rivaj | India, Maldives, South Africa, United States |
| Ривай | Russia, Ukraine |